El Abra

Overview

El Abra is a porphyry copper open-pit mine and processing facility located in the El Loa province in the Second Region of Chile, 47 miles north of the city of Calama, on the southern side of Cerro Pajonal, at 3,900 to 4,100 meters above sea level.

El Abra exhibits leachable oxide and sulfide mineralization.  The predominant oxide copper minerals are chrysocolla and pseudomalachite. The predominant primary sulfide copper minerals are bornite and chalcopyrite. There is a minor amount of secondary sulfide mineralization as chalcocite.

Processing is being done by cyanide heap leaching with pregnant solutions treated in a SX/EW facility that has a capacity of 500 million pounds of copper cathode per year from a 115,000 metric ton-per-day crushed leach circuit and a similar-sized ROM leaching operation.

Mining operations began in 1996. Production from the sulfide ore, which will be ramping up to approximately 300 million pounds of copper per year is expected to begin  in 2012 and will replace the current oxide copper production that is expected to decline over the next several years..

Location

Facilities of Sociedad Contractual Minera El Abra are in the El Loa province in the Second Region of Chile, 47 miles north of the city of Calama, on the southern side of Cerro Pajonal, at 3,900 to 4,100 meters above sea level.

The El Abra mine is located in a desert environment with rainfall averaging less than one inch per year and is in an active seismic zone.

Geology and Mineralization

El Abra is a large porphyry copper deposit.

The mining concessions cover more than 13,352 ha of land located in the Antofagasta region of Northern Chile, approximately 1,650 km north of Santiago. El Abra controls a total of 44,614 ha of mining claims covering the ore deposit, stockpiles, process plant, and water wellfield and pipeline. In addition, El Abra has acquired surface rights for the plant-mine access road, the wellfield, power transmission line, and for the water pipeline from the Salar de Ascotán. Acquisition of all additional surface area required for the future development of the sulfide project is in process.

The porphyry copper deposit has leachable oxide and secondary sulfide mineralization, and millable primary sulfide mineralization. The predominant oxide copper minerals are chrysocolla, pseudomalachite, copper-bearing clays and tenorite; chalcocite is the most important secondary copper sulfide mineral, bornite and chalcopyrite the dominant primary copper sulfide.

Mining & Operation

The El Abra operation consists of an open-pit copper mine and an SX/EW facility recovering up to 500 million pounds of copper cathode per year from a 130,000 ton-per-day crushed leach circuit and a similar-sized, ROM leaching operation.

The mining operation has sufficient equipment to move an average of 245,000 tons per day using a fleet of thirty-four 220-ton haul trucks loaded by four shovels with buckets ranging in size from 26 to 41 cubic yards.

The mine has been in operation since 1996.

The 2011 exploration results at El Abra indicate the potential for a significant additional sulfide resource.

Processing

El Abra has leachable oxide and sulfide mineralization. The SX/EW facility has a capacity of 500 million pounds of copper cathode per year from a 120,000 metric ton-per-day crushed leach circuit and a similar-sized ROM leaching operation.

Beginning in 2010, El Abra shifted from an oxide-leach, on-off pad operation to a bornite-dominant, sulfide-leach operation, where ore will be leached on a permanent pad. ROM ore mining and leaching will continue throughout the life of the property. 

Production from the sulfide ore, which will be ramping up to approximately 300 million pounds of copper per year is expected to begin in 2012 and will replace the current oxide copper production that is expected to decline over the next several years.

In 2012, the company announced that it is engaged in pre−feasibility studies for a potential large−scale milling operation at El Abra to process additional sulfide material and to achieve higher recoveries.

Environment & Community

One of the many initiatives that involve local communities is that the El Abra mine partnered with the Foundation for Women’s Promotion and Development to provide educational courses for economically vulnerable women. It has also launched a program to promote dental health for more than 120 children and approximately 20 teachers in five schools in indigenous communities. El Abra has also invested in teaching local kids English and computer skills.

With support from MineraEl Abra, Chile Army and community members, a local dumping ground was cleaned up, 150 trees were planted and the area was converted into a green community space.